Production of 1, 3-diene polymers in aqueous media

1,3-Dienes are polymerized in aqueous emulsion using 0.001 to 3% of a catalyst mixture of (a) a chelate complex of a metal with a 1,3-dicarbonyl compound, and (b) a cycloalkene having 5 to 12 ring carbon atoms, the metal being monovalent and/or divalent copper, silver or mercury, monovalent and/or trivalent thallium, trivalent chromium, manganese and cobalt, tetravalent cerium and titanium and/or divalent nickel, platinum and palladium, the ratio of cycloalkene to chelate compound being between 0.3 to 1 and 40 to 1. Specified catalysts are copper (II) or cobalt (III) aceto-acetate, manganese (III) benzoylacetone, copper (II) malonodialdehyde, cerium (IV) dibenzoylmethane, chromium (III)-3-methyl-butane-(1)-ol-(3) acetoacetate and thallium (1) acetylacetonate. Specified cycloalkenes are cyclopentadiene, cyclohexadiene, cycloheptadiene, cyclooctatetraene, cyclooctadiene-(1,5), cyclooctadiene -(1,4), cyclooctadiene-(1,3), the cyclodecatrienes and cycloheptatriene. The diene may be butadiene, isoprene, 2,3-dimethylbutadiene-1,3 or 2-phenylbutadiene while comonomers, e.g. acrylic, methacrylic, trimaric or maleic esters, styrene or substituted styrenes, vinyl ethers and esters may also be present. The polymerization may take place in the presence of added stabilizer, e.g. trinonylphenyl phosphite; it may take place continuously, preferably to conversions of 55 to 60%.